As defined by DNSSEC.net "it was designed to protect the Internet from certain attacks, such as DNS cache poisoning . It is a set of extensions to DNS, which provide: a) origin authentication of DNS data, b) data integrity, and c) authenticated denial of existence."
This is intended to protect people from far worse things (phishing, DNS poisoning, rewriting, etc) than having to resolve names through alternate servers. For an easier description wikipedia as always has us covered.
Happy Cinco DNSSEC Mayo!